There is a list that has around 100k items in a SharePoint Site Collection. This site has been customized to serve certain business requirements through visual webparts.

While, regular CRUD (create,update,delete) operations are done through CAML , I was recommended to use lists.asmx web service based operations in the visual webpart to achieve significant performance improvement over CAML.

I googled a little over this, but wasn't able substantiate this recommendation. Kindly point me in the right direction here.